Automatic stop for elevators.



P. L. MANLET.

AUTOMATIC STOP FOR ELEVATORS.

APPLICATION FILED SEPT-27. I911.

Patented Oct. 26, 1915.

PETER I. MANLET, OF ST. PAUL, MINNESOTA.

AUTOMATIC STOP FOR ELEVATORS.

Specification of Letters Patent.

Patented Oct. 26, 1915.

Original application filed May 9, 1911, Serial No. 625,948. Divided and this application filed September 27,

To all whom it may concern:

Be it known that I, PETER L. MANLET, a citizen of the United States, residing at St. Paul, in the county of Ramsey and State of Minnesota, have invented a new and useful Improvement in Automatic Stops for Elevators, of which the following is a specification.

My invention relates to improvements in automatic stops for elevators and its principal object is to provide a positive means for throwing off the power operating the elevator when the elevator car or the counter weights connected with it are carried beyond a predetermined point in their respective guide tracks. It frequently happens that an elevator operator is unable to shut ofi his power in time to prevent the car from rising too high in the elevator shaft, damaging the car and shaft and tending to break the elevator cable through the momentum of the counterweights. In a similar way the car may require automatic stopping at the bottom of its path to prevent damage to the car and counterweights.

Numerous devices are in use intended to apply brakes to the elevator car when it passes beyond its upper or lower limits, but which are frequently slow to operate or entirely ineffective. The device which I have invented operates positively and instantly to cut off the power operating the elevator and sets a brake to stop the elevator, thus preventing accidents through carelessness on the part of the operator or defective controlling devices.

In the drawings with which I have illustrated my invention and which form part of my specification, Figure 1 is a perspective view showing diagrammatically the operation of my device in connection with elevator counterweights and Fig. 2 shows the method of attaching my device in an elevator shaft.

In the drawings I have illustrated a main circuit switch A supplying power to the motor shaft B of the elevator car which moves in the car track C illustrated. A counterweight guide I) is shown in which slide the counterweights 2 connected to the elevator car in the ordinary manner by cables 3. The guides D are formed with grooves 4 carrying the ends of the counterweights 2. The track C also has a groove 5 or equivalent trackway to receive a guide Serial No. 651,629.

part on the elevator car E. The counter weight and its guides may be considered broadly as part of the car structure. My

device consists of a frangible peg or stop pin 6 fired in the guide groove 5 of the :track C 1n the path of the elevator car and carrying a flexible cord or chain 7 connecting with a similar peg 6 in the groove 4 of one of the guides D;

The motor shaft B has a friction wheel 8 in connection with it and brake arms 9 pivoted on a support 10 to grip the friction wheel 8 and stop the car connected with it. A lever arm 11 is pivoted on a support 12 and connected with the brake arms 9 to operate them. A weight F adjustably fixed 011 the lever 11 is adapted to force the lever down and operate the brake and is held out of operation normally by a flexible cord or chain 13 connected to the weight and passing over a suitable pulley 14C and connected to a pulley 14 running freely on the cord 7 which passes over pulleys 15 to give it suitable direction. A loose cord 17 is connected with the cord 13 and passed over suitable pulleys 18 to the handle 19 of the switch A to operate it simultaneously with the brake weight F.

The stops 6 may be placed at the top or bottom of the grooves 4 and 5 in which they are shown or otherwise placed in the path of the counterweight 2 of the car E in which ever manner is most convenient to place the desired limits of movement of the car in its shaft, such for instance as by placing one stop at the bottom of one counterweight groove of a pair and the other stop at the top of the companion groove.

This application is a division of the subject matter appearing in Patent Number 1,032,363, issued to me on the 9th day of July, 1912.

In accordance with the patent statutes I have described the principles of operation of my invention together with the apparatus which I now consider to represent the best embodiment thereof but I desire to have it understood that the construction shown is only illustrative and that the in vention can be carried out by other means and applied to uses other than those above set forth within the scope of the following claims.

Having described my invention, what I claim as new and desire to protect by Letters Patent is:

l. A device of the class set forth, comprising, in combination, elevator parts con- 5 sisting of a car and a counterweight connected'therewith, guides for said parts, actuating mechanism for said car, a brake for said car adapted when set to stop its mo- 'tion, a weight arranged on said brake to 10 set it by lowering, a frangible device in the path of one of said elevator parts to be broken when one of said parts moves be- ;yond a fixed limit of travel, and a connection between said frangible device and 15 weightholding said weight in raised position; until said frangible device is broken.

2. A device of the class set forth, comjprisin'g, in combination, elevator parts con-.

sisting of a car and a counter weight 0011- 20 nected therewith, guides for saidjparts, a'c

I Copies-of thispatent be obtained for tween said frangible device and operating means to asslst in holding the operating means with the brake in released position .until said'frangible device is broken.

In testimony whereof, I have signed my name to this specification, 1n the presence 10f two subscribing witnesses.

PETER L. MANLET.

Witnesses H. L. FIsCI-IER, 'PAUL S. SMiTH.

five cents each, by addressing the Commissioner of Patents, Washington, D503 

